1. Field of the Invention
The present invention relates to an improvement in or relating to a parallel processing system which permits the simultaneous operation of a plurality of processing units such as processors or memories, thereby attaining the high-speed processing of data, particularly color image data.
2. Description of the Prior Art
FIG. 11 shows a conventional parallel processing system comprising a plurality of processing units 1 to 6 connected to each other via buses. Also, FIG. 12 shows another conventional parallel processing system comprising a plurality of processing units 1 to 6 connected via a crossbar switch.
The perpetual connection type of parallel processing system as shown in FIG. 11 requires means to compensate for time difference in transporting data between different processing units due to different lengths of bus conductors between different processing units. Accordingly such parallel processing system is complicated, and the high-speed data transportation, and hence the high-speed data processing is hardly attainable.
As for the crossbar-switching type of parallel processing system as shown in FIG. 12 the number of the contacts of the crossbar switch will increase with the increase of the processing units to be handled. This will increase the size and cost of the whole system, and still disadvantageously data transportation distance will increase. As a matter of fact, the elongation of bus conductors is the cause for producing noise signals, and at the same time, making the data network sensitive to external noise signals.